The present invention relates generally to wireless receivers and more particularly to techniques for processing training signals in dual-carrier receivers.
EDGE (Enhanced Data Rates for GSM Evolution) is a wireless protocol that provides increased capacity and data transmission rates over conventional GSM networks. EDGE uses the same time-division multiple access (TDMA) frame structure, logic channels, and 200-kHz carrier bandwidth as standard GSM networks. Thus, in most instances, implementing EDGE requires a simple upgrade to an existing GSM network.
While EDGE provides improved performance over conventional GSM, including data speeds up to 200 kb/s, further improvements to EDGE, known as “Evolved EDGE,” are currently under development by the 3rd-Generation Partnership Project (3GPP). (For details, see 3GPP TR 45.912, “Feasibility study for evolved GSM/EDGE Radio Access Network (GERAN),” v. 7.2.0, Mar. 20, 2007, available as of the filing date of the present application at www.3gpp.org/FTP/Specs/html-info/45912.htm, hereinafter referred to as “Evolved EDGE Feasibility Study.”) With enhancements including receiver diversity, higher-order modulation, and a new dual-carrier mode, Evolved EDGE promises data rates exceeding 1 MBit/second under some circumstances. Because evolved EDGE also uses the same TDMA frame structure, logic channels, and carrier bandwidth as GSM networks, evolved EDGE may also easily be implemented on existing GSM networks. However, new mobile terminals must be designed to fully exploit these improvements.
Despite recent advances in wireless data network technologies, wireless data applications continue to demand higher data rates, with improved reliability. Major technology upgrades, such as from GSM/EDGE to Wideband CDMA, can be prohibitively expensive in many circumstances. Thus, there remains a need for continued improvements to existing wireless data networks.